Process for producing hydrogen bis(fluorosulfonyl)imide

Abstract

The present invention provides a process for producing hydrogen bis(fluorosulfonyl)-imide (HFSI) by fluorination of a liquid hydrogen bis(chlorosulfonyl)imide (HCSI) using a gaseous hydrogen fluoride. In some embodiments, HFSI that is produced is separated from the reaction mixture as a gas and is condensed to collect a liquid HFSI.

What is claimed is: 
     
       1. A process for producing hydrogen bis(fluorosulfonyl)imide (HFSI), said process comprising:
 adding a liquid hydrogen bis(chlorosulfonyl)imide (HCSI) and a gaseous hydrogen fluoride to a reaction apparatus under conditions sufficient to produce gaseous HFSI; and 
 removing said gaseous HFSI from the reaction apparatus. 
 
     
     
       2. The process of  claim 1 , wherein said liquid HCSI is added counter current relative to said gaseous hydrogen fluoride. 
     
     
       3. The process of  claim 1  further comprising the step of separating gaseous HFSI from hydrogen chloride byproduct. 
     
     
       4. The process of  claim 1 , wherein at least a portion of said HCSI is in the liquid phase, and the majority of the HFSI is in a vapor phase. 
     
     
       5. The process of  claim 1 , wherein said reaction condition comprises temperature and pressure conditions that are below the vapor pressure of HFSI but above the vapor pressure of HCSI shown in  FIG. 3 . 
     
     
       6. The process of  claim 1  further comprising the step of recovering at least a portion of the unreacted HCSI. 
     
     
       7. The process of  claim 6 , wherein said liquid HCSI comprises at least a portion of said recovered unreacted HCSI. 
     
     
       8. The process of  claim 1 , wherein said reaction apparatus comprises a series of a plurality of reaction chambers, and wherein each of said reaction chambers comprises a reactor for producing HFSI from HCSI and hydrogen fluoride; and a HFSI condenser for collecting said gaseous HFSI produced from each reactor. 
     
     
       9. The process of  claim 1 , wherein said process further comprises condensing said gaseous HFSI to produce a liquid HFSI. 
     
     
       10. A process for producing a liquid hydrogen bis(fluorosulfonyl)imide (HFSI), said process comprising:
 adding a liquid hydrogen bis(chlorosulfonyl)imide (HCSI) and a gaseous hydrogen fluoride to a reaction apparatus under conditions sufficient to produce gaseous HFSI, wherein said liquid HCSI is added counterflow to said gaseous hydrogen fluoride; 
 removing said gaseous HFSI from the reaction apparatus; and 
 condensing said gaseous HFSI to produce a liquid HFSI. 
 
     
     
       11. The process of  claim 10 , wherein said reaction condition comprises temperature and pressure conditions such that it is below the vapor pressure of HFSI but above the vapor pressure of HCSI. 
     
     
       12. The process of  claim 10 , wherein said process is a continuous process. 
     
     
       13. The process of  claim 10 , wherein the rate of addition of said gaseous hydrogen fluoride to said liquid HCSI is at least about 2:1. 
     
     
       14. The process of  claim 10 , wherein said gaseous HFSI is continuously removed from the reaction apparatus. 
     
     
       15. The process of  claim 14 , wherein gaseous HFSI that is removed from the reaction apparatus comprises unreacted HCSI. 
     
     
       16. The process of  claim 15 , wherein said unreacted HCSI is recovered and added to the reaction apparatus. 
     
     
       17. A process for producing hydrogen bis(fluorosulfonyl)imide (HFSI), said process comprising:
 adding a liquid hydrogen bis(chlorosulfonyl)imide (HCSI) and a gaseous hydrogen fluoride to a reaction apparatus under reaction temperature and pressure conditions to produce a mixture of gaseous HFSI and gaseous hydrogen chloride; and 
 removing said mixture of gaseous HFSI and gaseous hydrogen chloride from the reaction apparatus. 
 
     
     
       18. The process of  claim 17 , wherein the majority of unreacted HCSI remains as a liquid. 
     
     
       19. The process of  claim 17 , wherein said mixture of gaseous HFSI and gaseous hydrogen chloride is removed continuously from the reaction apparatus. 
     
     
       20. The process of  claim 17  further comprising the step of separating said gaseous hydrogen chloride from said mixture to produce a purified HFSI. 
     
     
       21. The process of  claim 20 , wherein said step of separating said gaseous hydrogen chloride from said mixture comprises the step of condensing said gaseous HFSI to produce a liquid HFSI and separating said gaseous hydrogen chloride from said liquid HFSI. 
     
     
       22. The process of  claim 17 , wherein said liquid HCSI is added in a counterflow direction to said gaseous hydrogen fluoride. 
     
     
       23. The process of  claim 17 , wherein said process is a continuous process. 
     
     
       24. The process of  claim 17 , wherein the stoichiometric ratio of addition of said gaseous hydrogen fluoride to said liquid HCSI is at least about 2:1.